Association of Albumin-Bilirubin Grade and Myosteatosis with its Prognostic Significance for Patients with Colorectal Cancer.

BACKGROUND: The albumin-bilirubin (ALBI) grade is a useful prognostic and predictive marker for patients with liver disease. Its clinical significance has been limited to patients with colorectal cancer (CRC). Furthermore, the association between the ALBI grade and skeletal muscle-related indices is unclear. METHODS: This study enrolled 1015 patients who underwent computed tomography (CT) scans within 31 days before surgery. The prognostic value of the ALBI grade in predicting overall survival (OS) was assessed using the Cox proportional hazards model. The correlation between the ALBI grade and the skeletal muscle index or radiodensity (myosteatosis) was evaluated. The predictive accuracy of ALBI alone and in combination with myosteatosis was compared using Harrell's concordance index (C-index). RESULTS: The significant prognostic factors for OS identified in the multivariable analysis were the ALBI group (low vs high: hazard ratio [HR], 1.566; 95 % confidence interval [CI], 1.174-2.089; p = 0.002) and myosteatosis (low vs. high: HR, 0.648; 95 % CI, 0.486-0.865; p = 0.003). The rate of low-grade myosteatosis increased as the ALBI grade increased. The C-index of combined ALBI and myosteatosis (0.650; 95 % CI, 0.618-0.683) was superior to that of ALBI alone (0.603; 95 % CI, 0.575-0.631; bootstrap incremental area under the curve [iAUC] mean difference, 0.047; 95 % CI, 0.012-0.070) and myosteatosis alone (0.608; 95 % CI, 0.577-0.640; bootstrap iAUC mean difference, 0.042; 95 % CI, 0.023-0.064). CONCLUSION: The ALBI grade is significantly associated with myosteatosis. The ALBI grade is a significant prognostic factor, and the combination of ALBI and myosteatosis show an additive value in discriminating survival of patients with CRC.

Preoperative magnetic resonance imaging-based prognostic model for mass-forming intrahepatic cholangiocarcinoma.

BACKGROUND & AIMS: As most staging systems for intrahepatic cholangiocarcinoma (iCCA) are based on pathological results, preoperative prognostic prediction is limited. This study aimed to develop and validate a prognostic model for the overall survival of patients with mass-forming iCCA (MF-iCCA) using preoperative magnetic resonance imaging (MRI) and clinical findings. METHODS: We enrolled a total of 316 patients who underwent preoperative MRI and surgical resection for treatment-naive MF-iCCA from six institutions, between January 2009 and December 2015. The subjects were randomly assigned to a training set (n = 208) or validation set (n = 108). The MRIs were independently reviewed by three abdominal radiologists. Using MRI and clinical findings, an MRI prognostic score was established. We compared the discrimination performance of MRI prognostic scores with those of conventional pathological staging systems. RESULTS: We developed an MRI prognostic score consisting of serum CA19-9 and three MRI findings (tumour multiplicity, lymph node metastasis and bile duct invasion). The MRI prognostic score demonstrated good discrimination performance in both the training set (C-index, 0.738; 95% confidence interval [CI], 0.698-0.780) and validation set (C-index, 0.605; 95% CI, 0.526-0.680). In the validation set, MRI prognostic score showed no significant difference with AJCC 8th TNM stage, MEGNA score and Nathan's stage. CONCLUSIONS: Our MRI prognostic score for overall survival of MF-iCCA showed comparable discriminatory performance with pathological staging systems and might be used to determine an optimal treatment strategy.

Serum leptin level and incidence of CKD: a longitudinal study of adult enrolled in the Korean genome and epidemiology study(KoGES).

BACKGROUND: Chronic kidney disease(CKD) is a major public health issue and is highly prevalent in the general population. Leptin is an adipose tissue-derived endocrine factor that has been associated with several metabolic factors involved in cardiovascular diseases. Several studies have investigated the association between leptin and renal diseases so far. But the results are conflicting between the studies. The objective of our study was to verify the direct association of serum leptin level with CKD development. METHODS: This prospective cohort study included 2646 adult aged 40-70 without CKD in the Korean Genome and Epidemiology Study(KoGES) across South Korea from November 2005 to February 2012. The primary outcome was the development of CKD as defined by National Kidney Foundation Kidney Disease Outcomes Quality Initiative (KDOQI). Multivariate stepwise logistic regression analysis was done to assess the independent associations, for with the incident of CKD as the dependent variable, in tertiles of leptin values. RESULTS: Among 1100 men and 1546 women with 2.8 mean years of follow-up, incidence of CKD was 18(1.63%) for men and 50(3.23%) for women. In the multivariate logistic regression models, individuals in the highest serum leptin tertile showed significant associations with risk of CKD after adjustment compared to the lowest tertiles in the population. The crude odds ratio for trend was 2.95(p = 0.004) for men. After adjusting for age, baseline eGFR variables showed correlation with statistical significance (OR for trend = 2.25, p = 0.037) for men. The same trends were also seen observed in all population and women also, but no statistical significance was found. CONCLUSIONS: Higher plasma leptin levels are associated with the incidence of CKD, independent of traditional factors such as age, baseline eGFR. Our results suggest that leptin may partly explain part of the reported association between obesity and kidney disease.

Gadoxetic acid-enhanced MRI of macrotrabecular-massive hepatocellular carcinoma and its prognostic implications.

BACKGROUND & AIMS: Despite the clinical and genetic significance of macrotrabecular-massive hepatocellular carcinoma (MTM-HCC), its characteristics on imaging have not been described. This study aimed to characterise MTM-HCC on gadoxetic acid-enhanced MRI and to evaluate the diagnostic accuracy and prognostic value of these imaging characteristics. METHODS: We enrolled 3 independent cohorts from 2 tertiary care centres. The 3 cohorts consisted of a total of 476 patients who underwent gadoxetic acid-enhanced MRI and surgical resection for treatment-naïve single HCCs. Independent review of histopathology and MRI by 2 reviewers was performed for each cohort, and inter-reader agreement was evaluated. Based on the result of MRI review in the training cohort (cohort 1), we developed 2 diagnostic criteria for MTM-HCC and evaluated their prognostic significance. The diagnostic performance and prognostic significance were validated in 2 validation cohorts (cohorts 2 and 3). RESULTS: We developed 2 diagnostic MRI criteria (MRIC) for MTM-HCC: MRIC-1, ≥20% arterial phase hypovascular component; MRIC-2, ≥50% hypovascular component and 2 or more ancillary findings (intratumoural artery, arterial phase peritumoural enhancement, and non-smooth tumour margin). MRIC-1 showed high sensitivity and negative predictive value (88% and 95% in the training cohort, and 88% and 97% in the pooled validation cohorts, respectively), whereas MRIC-2 demonstrated moderate sensitivity and high specificity (47% and 94% in the training cohort, and 46% and 96% in the pooled validation cohorts, respectively). MRIC-2 was an independent poor prognostic factor for overall survival in both training and pooled validation cohorts. CONCLUSIONS: Using gadoxetic acid-enhanced MRI findings, including an arterial phase hypovascular component, we could stratify the probability of MTM-HCC and non-invasively obtain prognostic information. LAY SUMMARY: Macrotrabecular-massive hepatocellular carcinoma (MTM-HCC) is a histopathologic subtype of HCC characterised by aggressive biological behaviour and poor prognosis. We developed imaging criteria based on liver MRI that could be used for the non-invasive diagnosis of MTM-HCC. HCCs showing imaging findings of MTM-HCC were associated with poor outcomes after hepatic resection.

Intralymphatic immunotherapy with tyrosine-adsorbed allergens: a double-blind, placebo-controlled trial.

BACKGROUND: Most previous studies used aluminum hydroxide-absorbed allergen extracts in evaluating the potential therapeutic roles of intralymphatic allergen-specific immunotherapy (ILAIT). In this study, we evaluated the therapeutic efficacy and safety of ILAIT with L-tyrosine-adsorbed allergen extracts of Dermatophagoides farinae, D. pteronyssinus, cat, dog, or mixtures thereof, in patients with allergic rhinitis induced by these allergens. METHODS: In this randomized, double-blind, placebo-controlled trial, study subjects received three intralymphatic injections of L-tyrosine-adsorbed allergen extracts (active group) or saline (placebo group) at 4-week intervals. RESULTS: Although ILAIT reduced daily medication use and skin reactivity to HDM and cat allergens at 4 months after treatment, overall symptom score on a visual analog scale (VAS), sinonasal outcome test-20 (SNOT-20), rhinoconjunctivitis quality of life questionnaire (RQLQ), daily symptom score (dSS), daily medication score (dMS), daily symptom medication score (dSMS), nasal reactivity to HDM allergen, and basophil activity to HDM, cat, and dog allergens at 4 months and 1 year after treatment were similar between the treatment and control groups. Intralymphatic injection was more painful than a venous puncture, and pain at the injection site was the most frequent local adverse event (12.8%); dyspnea and wheezing were the most common systemic adverse events (5.3%). CONCLUSIONS: ILAIT with L-tyrosine-adsorbed allergen extracts does not exhibit profound therapeutic efficacy in allergic rhinitis and can provoke moderate-to-severe systemic reactions and cause pain at the injection site. TRIAL REGISTRATION: clinicaltrials.gov: NCT02665754; date of registration: 28 January 2016.

Corona enhancement can substitute enhancing capsule in the imaging diagnosis of small (≤ 3 cm) HCCs on gadoxetic acid-enhanced MRI.

OBJECTIVES: This study aimed to elucidate the relationship between gadoxetic acid-enhanced magnetic resonance imaging (MRI) features-enhancing capsule, corona enhancement or hypointense rim-observed in hepatocellular carcinomas (HCCs). METHODS: Of the HCCs surgically confirmed during a 5-year period (2013-2017), ≤ 3-cm lesions (n = 83) in 78 patients were evaluated. Presence of corona enhancement and enhancing capsule on multiphasic dynamic imaging and presence of hypointense rim on hepatobiliary phase imaging were determined retrospectively by two independent observers. The relationship among the three imaging features was statistically analysed and correlated with the presence of histologic fibrous capsules, tumour differentiation and gross morphologic type. RESULTS: There was substantial overall interobserver agreement in determining the presence of the three imaging features. Sixty (72.3%) lesions had histologic fibrous capsule positively correlated with all three imaging features (p < 0.05). Corona enhancement was the most common (66.3%) feature followed by enhancing capsule (61.4%) and hypointense rim (33.7%), and the correspondence rate of enhancing capsule to corona enhancement was 68.6% (p = 0.004). Corona enhancement was more frequently observed in moderately differentiated HCCs than other lesions (p = 0.012) and not dependent (p = 0.465) on the tumour size, while enhancing capsule was significantly dependent on tumour size, as indicated by univariate (p < 0.001) and multivariate analyses (odds ratio, 4.241; p = 0.002). CONCLUSIONS: Among the capsular features, corona enhancement might closely relate to enhancing capsule in HCCs. Corona enhancement was not dependent on tumour size and had the highest incidence of appearance on gadoxetic acid-enhanced multiphasic dynamic MRI. KEY POINTS: • Enhancing capsule has a limited role in the LI-RADS categorisation during gadoxetic acid-enhanced MRI. • Appearance of corona enhancement is closely related to enhancing capsule and is not dependent on size of HCCs. • Corona enhancement can substitute enhancing capsule in the diagnosis of HCCs during multiple arterial and portal venous phase gadoxetic acid-enhanced MRI.

Preoperative prediction of postsurgical outcomes in mass-forming intrahepatic cholangiocarcinoma based on clinical, radiologic, and radiomics features.

OBJECTIVES: Current prognostic systems for intrahepatic cholangiocarcinoma (IHCC) rely on surgical pathology data and are not applicable to a preoperative setting. We aimed to develop and validate preoperative models to predict postsurgical outcomes in mass-forming IHCC patients based on clinical, radiologic, and radiomics features. METHODS: This multicenter retrospective cohort study included patients who underwent curative-intent resection for mass-forming IHCC. In the development cohort (single institution data), three preoperative multivariable Cox models for predicting recurrence-free survival (RFS) were constructed, including the clinical-radiologic, radiomics, and clinical-radiologic-radiomics (CRR) models based on clinical and CT findings, CT-radiomics features, and a combination of both, respectively. Model performance was evaluated in the test cohort (data from five institutions) using Harrell's C-index and compared with postoperative prognostic systems. RESULTS: A total of 345 patients (233, development cohort; 112, test cohort) were evaluated. The clinical-radiologic model included five independent CT predictors (infiltrative contour, multiplicity, periductal infiltration, extrahepatic organ invasion, and suspicious metastatic lymph node) and showed similar performance in predicting RFS to the radiomics model (C-index, 0.65 vs. 0.68; p = 0.43 in the test cohort). The CRR model showed significantly improved performance (C-index, 0.71; p = 0.01) than the clinical-radiologic model and demonstrated similar performance to the postoperative prognostic systems in predicting RFS (C-index, 0.71-0.73 vs. 0.70-0.73; p ≥ 0.40) and overall survival (C-index, 0.68-0.71 vs. 0.64-0.74; p ≥ 0.27) in the test cohort. CONCLUSIONS: A model integrating clinical, CT, and radiomics information may be useful for the preoperative assessment of postsurgical outcomes in patients with mass-forming IHCC. KEY POINTS: • The radiomics analysis had incremental value in predicting recurrence-free survival of patients with intrahepatic mass-forming cholangiocarcinoma. • The clinical-radiologic-radiomics model demonstrated similar performance to the postoperatively available prognostic systems (including 8th AJCC system) in predicting recurrence-free survival and overall survival. • The clinical-radiologic-radiomics model may be useful for the preoperative assessment of postsurgical outcomes in patients with mass-forming intrahepatic cholangiocarcinoma.

Subtraction Images From Portal Venous Phase Gadoxetic Acid-Enhanced MRI for Observing Washout and Enhancing Capsule Features in LI-RADS Version 2018.

OBJECTIVE. The purpose of this study is to validate the use of subtraction images derived from gadoxetic acid-enhanced MRI for observation of washout and enhancing capsule in the diagnosis of hepatocellular carcinoma (HCC). MATERIALS AND METHODS. For 120 histologically verified HCCs in 115 high-risk patients, the presence of washout and enhancing capsule in the portal venous phase (PVP) on conventional MR images with and without corresponding subtraction images was determined by two independent observers. The incremental value of subtraction imaging in upgrading the categories outlined in the Liver Imaging Reporting and Data System (LI-RADS) version 2018 for the diagnosis of HCC was analyzed for different subgroups of patients classified on the basis of lesion size (< 10 mm, 10-19 mm, ≥ 20 mm), unenhanced T1-weighted signal intensity, and arterial phase hyperenhancement (APHE) of the lesions. RESULTS. When conventional PVP images were compared with the combination of conventional and subtraction PVP images, only T1-weighted isointensity or hyperintensity significantly increased the detection of washout (eight vs 15 of 18 lesions; p = 0.0233). Detection of enhancing capsule was significantly increased (p < 0.05) regardless of various factors, except for a lesion size of less than 2 cm (five vs nine of 36 lesions; p = 0.1336). Two lesions (one LI-RADS category 3 lesion and one LI-RADS category 4 lesion) with APHE were upgraded to category 5 on the basis of a review of PVP subtraction images. CONCLUSION. PVP subtraction imaging during gadoxetic acid-enhanced MRI can upgrade LI-RADS categories for the diagnosis of HCC because of its superior ability in depicting enhancing capsule and the incremental benefit of showing washout.

Texture Analysis of Hepatocellular Carcinoma on Magnetic Resonance Imaging: Assessment for Performance in Predicting Histopathologic Grade.

OBJECTIVE: The aim of the study was to evaluate the performance of texture analysis for discriminating the histopathological grade of hepatocellular carcinoma (HCC) on magnetic resonance imaging. METHODS: Preoperative magnetic resonance imaging data from 101 patients with HCC, including T2-weighted imaging, arterial phase, and apparent diffusion coefficient mapping, were analyzed using texture analysis software (TexRAD). Differences among the histological groups were analyzed using the Mann-Whitney U test. The performance of texture features was evaluated using receiver operating characteristic analysis. RESULTS: Entropy was the most significantly relevant texture feature for distinguishing each histological grade group of HCC (P < 0.05). In ROC analysis, entropy with spatial scale filter 3 (area under curve the receiver operating characteristic curve [AUC], 0.778), mean with coarse filter (spatial scale filter 5; AUC, 0.670), and skewness without filtration (AUC, 0.760) had the highest AUC value on T2-weighted imaging, arterial phase, and apparent diffusion coefficient maps, respectively. CONCLUSIONS: Magnetic resonance imaging texture analysis demonstrated potential for predicting the histopathological grade of HCCs.

Sclerotic changes of cavernous hemangioma in the cirrhotic liver: long-term follow-up using dynamic contrast-enhanced computed tomography.

PURPOSE: To determine the intra- and extralesional factors that predict sclerotic degeneration of hepatic hemangiomas in the cirrhotic liver on long-term follow-up computed tomography (CT) examinations. MATERIALS AND METHODS: Fifty-seven hepatic hemangiomas (> 5 mm in diameter) in 41 cirrhotic patients, recruited over a 5-year period (January 2005-December 2009), were subjected to CT to determine which factors predict sclerotic contraction or degeneration in hemangiomas. Prior and follow-up CT examinations (from 2000 to 2018) were included to observe time-related changes. The patients' gender, age, cause of cirrhosis, progression of background liver cirrhosis, lesion size/location/contrast enhancement pattern, and serum aspartate transaminase to platelet ratio index were correlated with sclerotic changes of each lesion. RESULTS: According to the dynamic CT features, 36 of 57 (63%) hemangiomas were determined to have sclerotic changes during the follow-up period (1.1-14.4 years, median: 7.8 years), including 28 lesions (49%) reduced by ≥ 20% in diameter. In univariate analysis, age (p = 0.047) and morphological progression of background cirrhosis (p = 0.013) were significantly related to sclerotic change of hemangiomas. In the logistic regression analysis, only morphological progression of background liver cirrhosis independently predicted sclerotic change (odds ratio: 4.88, p = 0.007). With the exception of exophytic location free from size reduction (p = 0.023 in multivariate analysis), no other analyzed factors were significantly correlated with sclerotic changes. CONCLUSION: Overall, sclerotic changes of hepatic cavernous hemangioma followed the morphological progression of background liver cirrhosis, while exophytic lesions tended to be free of size reduction.

Retrospective Comparison of Renal Ultrasonographic and Clinical Findings in Patients with Rhabdomyolysis.

BACKGROUND: This study evaluated the ultrasonographic and clinical findings of two groups with rhabdomyolysis, who showed abnormal or normal ultrasonographic findings of kidneys. METHODS: Two groups (n = 78) of abnormal (A) and normal (B) renal ultrasonographic findings were included. Multiple laboratory findings were assessed within 2 days before or after ultrasonography. Student's t-test or Mann-Whitney U-test was used for statistical analysis. RESULTS: The variable causes of rhabdomyolysis were intense exercise, burn, operation, shivering, and drug intoxication, etc. Group A (n = 26; M:F = 19:7) showed enlarged both kidneys, increased parenchymal thickness, and increased (n = 23, 88.5%) or decreased (n = 3, 11.5%) cortical echogenicity. Group A also showed elevated blood urea nitrogen (BUN), creatinine, potassium, and prolonged activated partial thromboplastin time (aPTT), compared with those in Group B (n = 52; M:F = 36:16), and these results were statistically significant (P < 0.01). The myoglobin in serum and urine, creatine kinase, prothrombin time, dark urine, and microscopic hematuria were not statistically different between the two groups. CONCLUSION: Patients with elevated BUN, creatinine, potassium, and prolonged aPTT showed the ultrasonographic findings of acute kidney injury, but other parameters were not statistically different between the two groups.

Hepatic cavernous hemangiomas: long-term (> 5 years) follow-up changes on contrast-enhanced dynamic computed tomography or magnetic resonance imaging and determinant factors of the size change.

PURPOSE: To investigate the very long-term (> 5 years) follow-up changes of hepatic cavernous hemangiomas and to evaluate possible determinant factors for the changes. MATERIALS AND METHODS: Among 1115 consecutive patients suspected of having hepatic hemangiomas based on imaging features, 101 patients with comparable computed tomography or magnetic resonance imaging data during a 5-year follow-up interval in the Picture Archiving and Communication System were analyzed. Two radiologists independently determined the largest dimension of each lesion on axial images. In addition to background liver fibrosis or steatosis on imaging, histories of use of chemotherapeutic agents were checked from the patients' records. The final size change of the hemangioma was categorized into three groups compared with the initial diameter (increased, > 120%; no change, 80-120%; decreased, < 80%). RESULTS: Among the 101 hemangiomas, 32 lesions (31.7%) were enlarged and 21 lesions (20.8%) were shrunken during intervals of 60-157 (median, 81) months. Younger patients showed a higher prevalence of lesion enlargement (mean age: enlarged, 47.3 years; no change, 52.8 years; shrunken, 57.1 years; p = 0.003). In 15 patients with cirrhosis, the lesions (shrunken, n = 7; enlarged, n = 1) showed a higher tendency of size decrease (p = 0.009), whereas other factors did not show statistical significance (p > 0.05). Only a minor proportion (1%, n = 1) of the lesions showed size fluctuation during follow-up. CONCLUSION: During the long-term (5-13 years) follow-up, about 50% of the hepatic hemangiomas were enlarged or shrunken to > 20% of the initial diameter. Aside from the cirrhosis and aging factors, the size changes seemed sporadic.

Optimization of Split-Bolus CT Urography: Effect of Differences in Allocation of Contrast Medium and Prolongation of Imaging Delay.

OBJECTIVE: The purpose of this study was to find the optimal allocation ratio of contrast medium (CM) in split-bolus CT urography (CTU) and to investigate the effect of increased imaging delays for synchronous nephrographic-excretory phase imaging. SUBJECTS AND METHODS: One hundred ninety-two patients were randomly assigned to one of three protocols with different allocation ratios of CM: group A, 30% of CM at first bolus and 70% of CM at second bolus; group B, 70% and 30%; or group C, 50% and 50%. Saline (250 mL) was administered after the first CM bolus. Patients were subdivided by different imaging delay times (8, 10, 12, and 14 minutes). The attenuation values of the renal cortex and medulla were measured, and the opacification and maximal caliber of each segment of the ureter were evaluated. RESULTS: Renal cortical enhancement was significantly higher in group A (mean ± SD, 145.9 ± 17.5 HU) than group B (120.6 ± 106.3 HU). No significant difference in renal parenchymal enhancement was found with increased imaging delay times. The opacification and maximal caliber of each ureter segment showed no significant difference with different allocation ratios of CM or increased imaging delay times. CONCLUSION: A split-bolus CTU protocol with a larger CM volume administered at the second injection and an 8-minute imaging delay was the optimal protocol with regard to opacification of the ureter, renal parenchymal enhancement, and shorter examination time.

Multidetector CT findings of histopathologically proven peritoneal tuberculous cold abscesses.

PURPOSE: To evaluate the characteristic multidetector CT findings of peritoneal tuberculous (TB) cold abscesses. PATIENTS AND METHODS: The morphological characteristics of 48 peritoneal TB cold abscesses in 29 patients (male:female = 13:16; age range 16-75 years) were retrospectively evaluated. TB infection was histologically proven by acid fast bacilli (AFB) smear or culture, TB-polymerase chain reaction (PCR), or histopathological specimen diagnosis. RESULTS: Seventeen abscesses (35.4%) were present in the right perihepatic space, 10 (20.8%) in the left subphrenic space, 6 (12.5%) in the right subphrenic space, 4 (8.3%) in the pelvic cavity, 3 (6.3%) in the left perihepatic space, 3 (6.3%) in the right lower quadrant, and so on. The abscess contents ranged from 10.4 to 61.4 Hounsfield units. Internal septa (64.6%), central necrotic lymphadenopathy (55.2%), and TB coinfections in other organs (65.5%) were observed. TB infection was histopathologically confirmed from the surgical specimens in 17 patients and other 4 patients revealed the positive TB-PCR results from the peritoneal fluid. Ten patients (34.5%) had a recent history of TB peritonitis with ascites. CONCLUSION: Peritoneal TB cold abscesses were commonly found in the right perihepatic and subphrenic spaces and revealed higher density of internal content, frequent internal septa, central necrotic lymphadenopathy, and high TB coinfections in other organs.

Effect of increasing the flip angle during the hepatocyte phase of gadobenate dimeglumine-enhanced 1.5T MRI in cirrhotic patients with hepatocellular carcinoma.

PURPOSE: To evaluate the effects of increasing the flip angle during the hepatocyte phase of gadobenate dimeglumine-enhanced magnetic resonance imaging (MRI) in cirrhotic patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Sixty-three patients with liver cirrhosis underwent gadobenate dimeglumine-enhanced 1.5T MRI with 90-minute delayed hepatocyte phase with flip angles of 10°, 20°, 30°, consecutively. Relative enhancement and signal-to-noise ratio (SNR) of liver parenchyma at hepatocyte phase according to flip angle were calculated. The liver-to-lesion (low signal intensity HCCs, n = 63; ≥1 cm) and contrast-to-noise ratio (CNR) at the hepatocyte phase according to flip angle were calculated. Two radiologists independently assessed the presence of HCCs using a 5-point scale, and detection sensitivity of HCCs was calculated according to flip angle. RESULTS: The relative enhancement of hepatic parenchyma differed significantly according to flip angle (10°, mean relative enhancement = 0.69 ± 0.46; 20°, mean relative enhancement = 0.63 ± 0.47; 30°, mean relative enhancement = 0.49 ± 0.45; P = 0.043). The SNR of hepatic parenchyma was significantly different according to flip angle (10°, mean SNR = 26.2 ± 5.6; 20°, mean SNR = 25.3 ± 5.7; 30°, mean SNR = 22.8 ± 6.1; P = 0.004). The CNR of lesion was not significantly different according to flip angle (10°, mean CNR = 7.5 ± 6.6; 20°, mean CNR = 10.2 ± 6.9; 30°, mean CNR = 10.1 ± 7.1; P = 0.051). The sensitivities with 10° and 20° for HCCs were significantly higher than those with 30° for one reader (P < 0.05). CONCLUSION: In patients with cirrhosis, hepatocyte phase gadobenate dimeglumine-enhanced 1.5T MRI with 20° flip angle should be recommended rather than 10° and 30° flip angle.

Cerebral computed tomography angiography using a 70 kVp protocol: improved vascular enhancement with a reduced volume of contrast medium and radiation dose.

OBJECTIVES: To determine the feasibility of using a 70-kVp protocol compared with a 120-kVp protocol for cerebral CT angiography. An additional target was to investigate a possible reduction in the volume of contrast medium (CM) using the 70-kVp protocol. METHODS: Attenuation value and CNR for iodine were determined at various tube voltage settings using a phantom. Sixty-nine volunteers were randomly assigned to one of three protocols: group A (120-kVp and CM 64 mL), group B (70-kVp and CM 64 mL), or group C (70-kVp and CM 40 mL). The attenuation value, SNR, and CNR of cerebral arteries, subjective image quality, and radiation dose were compared among the groups. RESULTS: The vascular attenuation, SNR, and CNR of group B were significantly higher than those of group A. Group C had a significantly higher vascular attenuation than group A. Groups B and C were significantly better than group A with respect to subjective image quality. An effective dose of 70-kVp was 10 % lower than that of 120-kVp. CONCLUSIONS: Using 70-kVp improved arterial enhancement, SNR, and CNR, and provided better subjective image quality, using a 10 % lower effective dose. Furthermore, the 70-kVp protocol may both reduce volume of CM by 37.5 % and improve arterial enhancement. KEY POINTS: • Cerebral CT angiography at 70-kVp substantially improved vascular enhancement • Subjective image quality was better at 70-kVp, with lower radiation dose • The volume of contrast media can be substantially reduced at 70-kVp.

Feasibility of 5-minute delayed transition phase imaging with 30° flip angle in gadoxetic acid-enhanced 3D gradient-echo MRI of liver, compared with 20-minute delayed hepatocyte phase MRI with standard 10° flip angle.

OBJECTIVE: The purpose of this study was to compare 5-minute delayed transitional phase imaging using a 30° flip angle (hereafter, 5 min-FA30) and 20-minute hepatocyte phase imaging using a 10° flip angle (hereafter, 20 min-FA10) in gadoxetic acid-enhanced MRI for focal hepatic lesion detection and lesion-to-liver contrast-to-noise ratio (CNR), and to determine whether 5 min-FA30 could replace 20 min-FA10 with a 15-minute time saving. MATERIALS AND METHODS: One hundred sixteen patients with 282 focal hepatic lesions (size range, 0.2-12.5 cm; malignant, n = 146; benign, n = 136) underwent gadoxetic acid-enhanced MRI with 5 min-FA30 and 20 min-FA10 with a 3D T1-weighted gradient-echo sequence. Three radiologists independently assessed the presence of focal hepatic lesions using a 4-point scale, and detection sensitivity of focal hepatic lesions was calculated. Lesion-to-liver CNRs were calculated and compared in two image groups. RESULTS: There was no significant difference in detection sensitivity of focal hepatic lesions for all three readers between 5 min-FA30 (mean, 95.4%) and 20 min-FA10 (mean, 95.6%), irrespective of lesion size or malignancy. The mean CNR on 5 min-FA30 (167.9 ± 84.1) was significantly higher than that on 20 min-FA10 (160.2 ± 79.5). However, the mean CNR difference between the two image groups was relatively small (7.8 ± 41.9). CONCLUSION: Compared with 20 min-FA10, 5 min-FA30 provided higher CNR and similar sensitivity. These findings indicate that 5 min-FA30 could replace 20-min delayed hepatocyte phase imaging using a 10° flip angle with similar diagnostic performance and 15 minutes of time saving.

Evaluation of lateral pelvic nodes in patients with advanced rectal cancer.

OBJECTIVE: The purpose of this article is to discuss the importance of lateral pelvic lymph node metastasis as a predictor of local recurrence and survival in patients with advanced rectal cancer. CONCLUSION: Prediction of lateral pelvic nodal staging on MRI shows high accuracy compared with the other imaging modalities. Diffusion-weighted MRI or (18)F-FDG PET/CT may be helpful to assesses lateral pelvic lymph node metastasis.

Usefulness of a lead shielding device for reducing the radiation dose to tissues outside the primary beams during CT.

PURPOSE: This study was done to investigate the efficacy of a lead shield in protecting the tissues outside the primary beams, such as the breast and thyroid, by measurement of the entrance skin dose during CT of the brain, neck, abdomen, and lumbar spine. MATERIALS AND METHODS: Institutional Review Board approval was obtained. This study included 150 patients (male:female 25:125, age range 15-45 years). In females, brain, lumbar spine, and abdominal CT scans, pre-/post-contrast neck CT scans, and post-contrast liver dynamic CT scans were performed. In males, brain CT scans only were performed. Breast shielding was performed in all females, and thyroid shielding was conducted in patients with brain CT. During all CT studies, the left breast or left thyroid was shielded using a lead shield, and the contralateral side was left unshielded. Thus, each breast or thyroid measurement had its own control for the same demographic data. The efficacy of the shielding of both breasts and thyroids during CT was assessed. RESULTS: During brain, abdominal, lumbar, pre-/post-contrast neck, and post-contrast liver dynamic CT, 33.5, 26.0, 17.4, 26.5, and 16.2 % of the breast skin dose were reduced, respectively. During brain CT, the thyroid skin dose was reduced by 17.9 % (females) and 20.6 % (males). There were statistically significant differences in the skin doses of shielded organs (p < 0.05). Breast shielding during neck and liver dynamic CT was the most effective compared with breast or thyroid shielding during other CT scans. CONCLUSIONS: We recommend breast shielding during neck and liver dynamic CT in young female patients to avoid unnecessary radiation exposure.

Follistatin-like 1 is a myokine regulating lipid mobilization during endurance exercise and recovery.

OBJECTIVE: The aim of this study was to investigate the role of the follistatin-like 1 (Fstl1) and disco-interacting protein 2 homolog A (DIP2a) axis in relation to lipid metabolism during and after endurance exercise and to elucidate the mechanisms underlying the metabolic effects of Fstl1 on adipocytes, considering its regulation by exercise and muscle mass and its link to obesity. METHODS: Twenty-nine sedentary males participated in endurance exercise, and blood samples were collected during and after the exercise. Body composition, Fstl1, glycerol, epinephrine, growth hormone, and atrial natriuretic peptide were measured. 3T3-L1 adipocytes, with or without DIP2a knockdown, were treated with Fstl1 to assess glycerol release, cyclic AMP/cyclic GMP production, and hormone sensitive lipase phosphorylation. The association between DIP2a gene expression levels in human adipose tissues and exercise-induced lipolysis was examined. RESULTS: Fstl1 levels significantly increased during endurance exercise and following recovery, correlating with lean body mass and lipolysis. In 3T3-L1 adipocytes, Fstl1 increased glycerol release, cyclic GMP production, and hormone sensitive lipase activation, but these effects were attenuated by DIP2a knockdown. DIP2a gene expression in human adipose tissues correlated with serum glycerol concentrations during endurance exercise. CONCLUSIONS: Fstl1 is a myokine facilitating lipid mobilization during and after endurance exercise through DIP2a-mediated lipolytic effects in adipocytes.